In the above-mentioned valve opening-closing timing control device, the front member includes multiple bearing surfaces in the form of conical surfaces provided so as to be attached with the countersunk head screws to the driving rotating body.
Therefore, the projecting amount of bolt heads from the front member is reduced, as compared to the case where the front member is attached with hexagonal bolts or the like to the driving rotating body, in which their bolt heads are brought into pressure contact with the flat surface of the front member. Thus, the installation thereof is easy, even into a narrow installation space, which is advantageous (see, for example, Patent Document 1).
This valve opening-closing timing control device includes the torsion coil spring that is engaged between the following rotating body and the front member, and biases the following rotating body in the advance direction or the retarded direction with respect to the driving rotating body, wherein the front member includes the engaging part capable of engaging the end of the torsion coil spring with the torsion coil spring in a twisted state.
Therefore, when the front member is attached with multiple countersunk head screws to the driving rotating body, the countersunk head screws are tightened with torsional force of the torsion coil spring acting on the front member.